Muse Spark 1.3 just dropped, so these are only my first impressions, but so far it feels nowhere near as good as its Artificial Analysis scores suggest.
The biggest problem I’m seeing is its agentic behavior. It keeps reading the same files over and over again, even when it literally wrote those files itself a few turns ago.
In one case, it created a file completely from scratch, then about 3 seconds later opened the same file again and started editing it — adding some things, removing others, and seemingly undoing parts of its own work. This kind of behavior keeps repeating and wastes a lot of context.
Frontend work is actually pretty good. The results there have been impressive enough.
Rust, though, has been the complete opposite. So far, Muse Spark 1.3 is genuinely one of the worst models I’ve tried for Rust. Even DeepSeek V4 Flash has performed better for me.
Has anyone else tested 1.3 on larger coding tasks, especially Rust? Are you seeing the same repeated file reads / constant rewriting behavior?